Parkinson, 78, said he was diagnosed in May after a routine checkup. He is receiving radiotherapy treatments and expects to make a full recovery, the BBC said.
"It was a great shock, but I have been told to expect to make a full recovery," he said.
He said he has not felt any pain or discomfort from the treatment.
Parkinson, known as Parky to his fans, also urged men to pay more attention to their health .
"I don't want to trivialize it, but men know when there's a problem. I have been lucky, but men are silly about their health. Get it checked out -- it might be something else."
He retired in 2007.
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